This invention relates to a half-fitting prevention connector in which when a pair of male and female connectors are fitted together, a half-fitted condition of the male and female connectors is detected by determining that whether or not a fitting detection member, mounted on one of the two connectors, can be slid into a proper fitting detection position.
FIGS. 4 and 5 show a related half-fitting prevention connector. The half-fitting prevention connector 60, shown in FIGS. 4 and 5, includes a male connector 70, a female connector 80, and a fitting detection member 90.
The female connector 70 includes a tubular portion 71 within which tab terminals 72 are provided, and a projection 73 is formed on the tubular portion 71. The male connector 70 is connected to a connector of a control circuit or the like, and the tab terminals 72 are electrically connected to this control circuit.
The female connector 80 has tab-receiving terminals 81 received therein, and tab holes 82 each for guiding the tab terminal 72 of the male connector 70 into the tab-receiving terminal 81 are formed in a front end of the female connector. A lock arm 83 is formed on the female connector 80, and can be disposed on an outer peripheral face of the tubular portion 71 of the male connector 70, and can be retainingly engaged with the projection 73. The tab-receiving terminals 81 are electrically connected to an electrical equipment part.
The fitting detection member 90 is mounted on the outer periphery of the female connector 80 so as to slide in a direction of fitting of the male and female connectors 70 and 80 relative to each other. The fitting detection member 90 has a retaining arm 91.
In the half-fitting prevention connector 60, when the retaining arm 91 of the fitting detection member 90 is retainingly engaged with the lock arm 83 of the female connector 80, there is achieved an initial condition in which the front end portion of the female connector 80 projects beyond the end of the fitting detection member 90 as shown in FIG. 4. In this initial condition, the lock arm 83 of the female connector 80 is retainingly engaged with the retaining arm 91 of the fitting detection member 90, and therefore the female connector 80 can not slide relative to the fitting detection member 90.
Then, when the tubular portion 71 of the male connector 70 is inserted between the fitting detection member 90 and the female connector 80 as shown in FIG. 5, the projection 73 of the male connector 70 pushes the lock arm 83 up, so that the fitting of the female connector 80 on the male connector 70 proceeds while the lock arm 83 of the female connector 80 slides on the projection 73 of the male connector 70.
In this fitted condition (half-fitted condition), the tab terminals 72 are inserted in the tab holes 83, respectively, but are not yet positively electrically connected to the tab-receiving terminals 81, respectively.
When the fitting of the female connector 80 on the male connector 70 further proceeds, the lock arm 83 of the female connector 80 slides over the projection 73 of the male connector 70, and is brought into retaining engagement with this projection 73. Then, the retaining arm 91 of the fitting detection member 90 slides over the projection 73 of the male connector 70 and the lock arm 83 of the female connector 80, and advances.
As a result, the lock arm 83 of the female connector 80 is held between the projection 73 of the male connector 70 and the retaining arm 91 of the fitting detection member 90, thereby achieving a completely-fitted condition. In this completely-fitted condition, the tab terminals 71 are positively electrically connected to the tab-receiving terminals 81, respectively.
In the above half-fitting prevention connector 60, however, in a case that the connector shifts from the half-fitted condition to the completely-fitted condition, that is, when the lock arm 83 of the female connector 80 slides over the projection 73 of the male connector 70, a frictional force between the lock arm 83 and the projection 73 is large. Therefore, there has been encountered a problem that the advance of the female connector 80 stops, so that the tab terminals 72 are electrically connected respectively to the tab-receiving terminals 81 in an unstable electrical connecting condition.
Particularly when the tab terminals 72 and the tab receiving terminals 81 are used as signal lines so as to feed a very small current, there has been encountered a problem that an error develops.